Economizer is a device installed at the lower part of the flue at the tail of the boiler. It is mainly used to recover the waste heat in the flue gas. Through heat exchange, the boiler feed water is heated into saturated water under the drum pressure, thereby improving the thermal efficiency of the boiler and saving energy. The working principle of the economizer is based on heat conduction, convection and radiation. The heat of the flue gas is transferred to the low-temperature feed water through metal tubes or metal walls to increase the feed water temperature entering the drum.

Types and structures of boiler economizers

Economizers are mainly divided into tube economizers and plate economizers.

‌Tube economizer‌: It is composed of many parallel metal tubes. The flue gas flows outside the tube and the fluid flows inside the tube to achieve the purpose of heat exchange. This structure has strong heat conduction capacity and high thermal efficiency.

‌Plate economizer‌: It is composed of a series of metal plates. The flue gas and heat exchange medium flow between the plates respectively and exchange heat through the plate walls. The plate economizer has a compact structure and occupies a small area.

Advantages of Economizer Application

‌Energy saving and emission reduction‌: By recovering the waste heat in the flue gas, reducing fuel consumption, lowering the exhaust temperature, and reducing heat loss, the purpose of energy saving and emission reduction can be achieved.‌

‌Improving combustion efficiency‌: The preheated air enters the boiler, which can improve the combustion efficiency and reduce fuel consumption.‌

‌Wide application‌: Economizers are widely used in various industries and the power industry, especially in boiler systems, playing a vital role.‌